1. Field of the Invention
The present invention relates to a cable with a plug, a control circuit and a substrate.
2. Description of the Related Art
In general, when charging a secondary battery installed in an electronic device (which is hereinafter referred to as a “secondary-cell-side electronic device”), the secondary battery is charged by connecting the secondary-cell-side electronic device to an electronic device that becomes a power source (which is hereinafter referred to as a “power-source-side electronic device”) through a feed cable. On this occasion, a plug provided at an end of the feed cable is connected to the secondary-cell-side electronic device, and a plug provided at the other end is connected to the power-source-side electronic device.
When performing this connection, for example, if the plugs are inserted in an opposite manner, the feed cable is liable to produce heat. Conventionally, as disclosed in Japanese Laid-Open Patent Application Publication No. 2006-171860, there has been a protective device for preventing the heat generation of the feed cable configured to provide a fuse in an electronic device and to interrupt the power feeding by causing the fuse to be cut due to the produced heat.
Moreover, Japanese Laid-Open Patent Application Publication No. 2000-339067 discloses a protective device installed in an IC (Integrated Circuit) that controls charging and is provided in the middle of a feed cable, which is configured to interrupt the power feeding when a temperature of the feed cable is equal to or higher than a predetermined temperature.
However, when using the fuse, once the fuse is cut due to an abnormal temperature, the electronic device cannot be used until the fuse is replaced by new one. In addition, because installing the fuse in the feed cable is difficult, the heat generation of the feed cable cannot be directly detected.
In the configuration of detecting the abnormal temperature by using the protective device installed in the middle of the feed cable, the generated heat is measured by a temperature sensor installed in the middle of the feed cable, and the power feeding is interrupted based on the measured heat. Accordingly, when an abnormal temperature is generated at a location other than the location including the temperature sensor of the feed cable, the abnormal temperature cannot be detected promptly.